1. Field of the Invention
This invention relates to an automobile LED driving device to drive and control the automobile LED [Light Emitting Diode] (e.g., a rear lump or a room light).
2. Description of Related Art
FIG. 18 is a circuit diagram illustrating a conventional example of the automobile LED driving device. With respect to an automobile LED driving device in accordance with this conventional example, a switch 201 is turned ON when turning ON the tail lump and the switch 202 is turned OFF. As a result, when turning ON the tail lump, a current I1 flows from a battery 100 to a light emitting diode row 600 via a switch 201, a diode 301, a resistor 401, and a resistor 500. On the other hand, when turning ON the brake lump, the switch 201 is turned OFF and the switch 202 is turned ON. As a result, when turning ON the brake lump, a current I2 flows from the battery 100 to the light emitting diode row 600 via the switch 202, the diode 302, the resistor 402, and the resistor 500. Here, the resistor 402 has a smaller resistance than the resistor 401. Accordingly, the current I2 flowing when turning ON the brake lump becomes larger current value than the current I1 flowing when turning ON the tail lump, the light emitting diode row 600 emits the light brighter when turning ON the brake lump than when turning ON the tail lump.
In addition, as an example of related conventional technique to the aforementioned technique, Japanese patent publication No. 2006-313808 can be listed.
However, with respect to the aforementioned conventional automobile LED driving device, to adjust the light emission amount of the light emitting diode row 600 when both of turning ON the tail lump and the break lump, resistances of the resistors 401 and 402 located on the current way to the light emitting diode row 600 have to be adjusted, it is difficult to adjust the light emission amount of the light emitting diode row 600 highly accurately.